OSCAR Pistorius has appeared to briefly break down in court as his defence lawyer argued that Reeva Steenkamp was so badly brain damaged by the gunshot to her head she couldn’t possibly have screamed for help.

The athlete’s lawyer Barry Roux made the claims in response to a neighbour’s testimony that she heard a woman’s screams after shots were fired on the night the model was killed.

He told the court: “We will have experts state that there was serious brain damage after the shot to the head, that it would not have been possible for her to scream at all.

“With the head shot, she would have dropped down immediately.”

The Paralympian was seen bent double in the dock, with his hands behind his head, as the court heard details of the bullets hitting Miss Steenkamp and the removal of fragments from her head during the post-mortem.

Upset in court ... Oscar Pistorius rubs his eyes at the North Gauteng High Court in Pretoria, South Africa, for the second day of his trial. Picture: AFPSource: AFP

He then buried his head in his hands briefly before pulling a handkerchief from his jacket pocket to wipe his eyes and nose.

His emotional reaction comes after a key witness who testified to hearing screams then gunshots from Oscar Pistorius’s home also broke down and wept in court, saying she still relives the “terrifying screams’’ she heard.

At the second day of the South African Paralympian’s murder trial, a shaken Michelle Burger sobbed after tough cross-examination, saying the events of Valentine’s Day 2013, when Reeva Steenkamp was killed, still haunted her.

“When I’m in the shower, I relive her shouts. The terrifying screams,’’ she told the North Gauteng High Court.

Oscar Pistorius ... blocks his ears inside the high court on the second day of his trial in Pretoria, South Africa. Picture: AP Photo/Kim LudbrookSource: AP

The university lecturer has testified that she heard screams, then gunshots, then more screams from Pistorius’s Pretoria home less than 200 metres away from her own.

Pistorius took notes during testimony and huddled with lawyers during adjournments. His collected demeanour contrasted with his sometimes distraught behaviour during a bail hearing last year, when he sobbed in court. At one point he covered his ears, but it wasn’t clear why.

The only time Pistorius looked anxious was when he prepared to leave the courthouse after the day’s proceedings were adjourned. Surrounded by police officers and private bodyguards, Pistorius ducked his head and walked out as one of the officers said: “Let’s go, guys.’’

Outside, television cameras, photographers and others swarmed around him.

Pistorius, 27, a double amputee known as the “Blade Runner’’ for his carbon-fibre running blades, has pleaded not guilty to murder and three unrelated gun charges.

While admitting killing Steenkamp, the sprinter described it as a “tragic accident’’, denying murderous intent and saying “we were in a loving relationship’’.

If found guilty of premeditated murder, Pistorius faces 25 years in South Africa’s notoriously brutal jails and an abrupt end to his glittering sporting career.

His defence came under further attack when another neighbour Estelle van der Merwe, who lives less than 100 metres away, told the court she heard arguing coming from Pistorius’s home on February 14, 2013.

“I woke up the morning at 1:56am to sounds of someone talking loudly and fighting,’’ she told the court. “It lasted about an hour.’’

Later she recalled waking up to the sound of loud bangs.

Ms Van der Merwe has yet to come under cross-examination

Ms Burger’s husband, Charl Johnson, also took the stand, telling judge Thokozile Masipa that a woman’s screams woke him up and that he ran to his balcony, less than 200 metres from Pistorius’s home.

“At that point the fear and intensity of her voice escalated and it was clear that this person’s life was in danger,’’ he said.

“That’s when the first shots were fired,’’ although Johnson could not recall how many.

Both Johnson and Burger also said they heard a male person shout for help, a point that was seized upon by the defence as evidence Pistorius was calling for help.

As well as relentlessly trying to pick holes in the testimony of state witnesses, the defence is also expected to call into question the reliability of the prosecution’s forensics.

Pistorius walked free on bail a year ago as the chief detective and the prosecution’s star witness, Hilton Botha, was sacked amid a scandal over botched handling of evidence.

A single judge, Thokozile Masipa, aided by two assistants, will rule in the case, which has already been likened to the murder trial of American footballer OJ Simpson over the killing of his ex-wife and a friend in 1995.

Tough gig ... Barry Roux, legal representative for Oscar Pistorius, on the second day of the murder trial.Source: AFP

With a landmark ruling allowing the trial to be partly televised, Ms Masipa slammed the media for showing a photograph of Ms Burger.

The witness had requested her image not be shown while the audio of her testimony was broadcast.

“I must say this is very disturbing, I am warning the media, if you do not behave, you will not be treated with soft gloves,’’ she warned.

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